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There is a Citrix XenServer 5.5 (HP ML370 G5, Xeon 2GHz) on this Server there is a Windows Guest (Windows 2008 R2 x64) under Properties I set 4 CPU Cores with max prio. But if I check with CPU-Z the performance of the CPU from Host there is set the right CPU (XEON 2GHz) but with only 600MHz what is wrong with this Guest.

The /proc/cpuinfo from Citrix XenServer:

processor : 0
vendor_id : GenuineIntel
cpu family    : 6
model     : 15
model name    : Intel(R) Xeon(R) CPU           E5335  @ 2.00GHz
stepping  : 7
cpu MHz       : 2000.016
cache size    : 4096 KB
fdiv_bug  : no
hlt_bug       : no
f00f_bug  : no
coma_bug  : no
fpu       : yes
fpu_exception : yes
cpuid level   : 10
wp        : yes
flags     : fpu de tsc msr pae cx8 apic mtrr cmov pat clflush acpi mmx fxsr sse sse2 ss ht constant_tsc up pni vmx
bogomips  : 4002.63

Here is the Outout of CPU-Z from Windows Guest:

enter image description here

On another Citrix XenServer under Citrix XenServer 6.1 with the same machine it works fine. Is this a failure from Citrix Xenserver or of HP Hardware?

Update The Core speed don't increase if the CPU has load: enter image description here

Update 2 This is the Output of xenpm

# xenpm get-cpufreq-states
Xen cpuidle is not enabled!
Xen cpufreq is not enabled!
share|improve this question
Have you installed the XenServer Tools on this Windows Guest? – plasmid87 Nov 21 '13 at 11:06
Also, this could be related - HP servers can be set to balance energy consumption against performance. They're supposed to scale according to demand, but this doesn't always happen properly. What have you got set in the BIOS for this HP machine? – plasmid87 Nov 21 '13 at 11:11
No there are no XenServerTools installed because it is a Console Installation of Windows Server. What BIOS Information are interesting for this issue? After load BIOS defaults I only activate the Virtualization Properties. – kockiren Nov 21 '13 at 12:01
If you load the processor, does the clock speed increase? A 6x multiplier is very low. – Nathan C Nov 21 '13 at 13:58
I update my post with core speed on max CPU load – kockiren Nov 21 '13 at 14:49

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